AR 3435 White light image with the C9.25 from 23rd Sept 2023

[Pete Presland]

Very small window of opportunity on Sunday, unfortunately the seeing was not great either. AR3435 was nicely positioned in the centre of the disc, so hopefully some granulation as well would be visible.

I managed extracted some decent detail on the 4th run and last run of the morning, during a slightly more stable couple of minutes. 

The usual set up C9.25 (when conditions allow), x3 Barlow, ASI174mm. 60 second capture stacking 5%

[knobby]

Very nice ! What filter did you use ?

[Pete Presland]

Whoops i normally say 🙂 it is a home made 200m diameter Baader OD3.8 Film Filter.

[knobby]

I've been thinking of trying that myself, it's a shame that the film is too narrow for the 9.25.

Have you any pictures ?

[Mandy D]

17 minutes ago, knobby said:

I've been thinking of trying that myself, it's a shame that the film is too narrow for the 9.25.

Have you any pictures ?

You don't actually need to make the filter full aperture and the A4 sheet at 8.27 inches width is not far off that. Even allowing for mounting, you'll still have a decent size filter.

Rother Valley do larger sheets at 100 x 50 cm, too.

https://www.rothervalleyoptics.co.uk/baader-astrosolar-nd50-safety-film-sheet.html

Just select the size from the dropdown.

Edited September 26, 2023 by Mandy D

[knobby]

Cheers Mandy, I've seen that ... but cringed at the price !

I guess It is something thats made to fine tolerances so the cost isn't bad really.

I do have a fair size chunk of film left from my 72ED diy job.

[Nigella Bryant]

For imaging you need the ND3.8 but shouldn't use it for visual, NEVER. ND5.0 is good for visual. 

[Pete Presland]

21 hours ago, knobby said:

I've been thinking of trying that myself, it's a shame that the film is too narrow for the 9.25.

Have you any pictures ?

 

[Pete Presland]

Here is the link to the homemade built filter. 200mm is probably too large on a lot of occasions when the seeing is not god enough to support it.